Apparatus for expanding bags



April 5,1966 RQRAGAN 1 3,243,937

APPARATUS FOR EXPANDING BAGS Filed Nov. 5, 1962 2 Sheets-sheaf, l

INVENTOR ROBERT O. fFAGA/V ATTORNEY j! if April 5, 1966 R. o. RAGANAPPARATUS FOR EXPANDING BAGS 2 Sheets-Sheet 2 Filed Nov. 5, 1962 L--Z7\1 F70. 7

United States Patent 3,243,937 APPARATUS FOR EXPANDING BAGS Robert O.Rag'an, Oak Park, 111., assignor, by mesne assignments, to Waldorf PaperProducts Company, St. Paul, Minn., a corporation of Minnesota Filed Nov.5, 1962, Ser. No. 235,225 13 Claims. (Cl. 53384) This invention relatesto an improvement in method and apparatus for expanding bags and dealsparticularly with a method of automatically squaring up the closed endsof bags, and an apparatus for carrying through the method.

Many products are merchandised in bags which may or may not havetransparent portions so'that the contents may be viewed. While such bagsare often times filled automatically and are often automatically closed,they are usually set up by hand, as a rather complicated mechanism isusually required to feed each bag into an apparatus capable of expandingthe bag and forming the square end thereon. While a semi-automaticmechanism may he used, it is usually just about as easy for the operatorto expand the bag manually as to place each individual bag on theexpanding apparatus. Thus the cost of the paci aging operation is quitematerially increased by the labor costs involved in opening the bags.

I have found that if the series of bags are formed by applying a spot ofadhesive near the mouth of the bags and between adjacent superimposedbags, the bags may be handled with comparative ease. The bags areshipped and stored in a flat shape in the usual manner. However, whenthe end bag of the series is grasped and pulled away from the others,the bags tend to fold open much in the manner of a bellows of anaccordion, the pulling action of each bag acting to open and expand thenext adjacent bag. With this arrangement, the bags form a connectedchain and the bags may be readily fed into position over spaced mandrelsmounting on a moving conveyor. The mandrels are of the expandable andcontractable type, so that after the bags are mounted upon the mandrels,the mandrels can be expanded to form the bag into rectangular shape.Means are provided for flattening the ends of the open bags so as toform a square bag end. If desired, the bags may be heat sealed in squareform to prevent any chance of their returning to their folded state. Thebags of the type normally used include a pair of side wall panels whichare connected along their contiguous edges by a pair of inwardly foldedgusset panels. By applying a spot of adhesive between each pair of bagsin a series, a pull upon the leading edge of the side panel of theforemost bag wiil tend to pull the flat sides of the bag apart, foldingthe gusset panels toward a common plane. As the opposite side wall isconnected to the forward panel of the next bag, when the foremost bag isopened, a further pull will tend to open the second bag, and so onthroughout the length of the chain of bags. The bags are supplied inthis manner and connected in as long chains as is practical. In placingthe bags into the hopper of the bag opening mechanism, a spot ofadhesive may be applied between the last bag of one chain and theforward bag of the next so that the bag opening apparatus will operatecontinuously.

A feature of the present invention resides in the method of placing thebags upon spaced mandrels while the mandrels are collapsed so that thebags are elongated beyond their normal width by the connecting spots ofadhesive. However, when the mandrels are expanded, the adhesiveconnection is broken, and from this point onward the bags are individualbags and operate as such.

These and other objects and novel features of the present invention willbe more clearly and fully set forth in the following specification andclaims:

ice

In the drawings forming a part of the specification;

FIGURE 1 is a diagrammatic side elevational view of an apparatus forerecting bags.

FIGURE 2 is a side elevational view of a series of bags in slightlyexpanded relation.

FIGURE 3 is a bottom panel view of a series of bags in more greatlyexpanded form.

FIGURE 4 is a perspective view showing the position of a single bag uponan expandable and contractable mandrel.

FIGURE 5 is a view similar to FIGURE 4 showing the mandrel in expandedposition.

FIGURE 6 is an end elevational view of a contracted mandrel showing theguides for expanding the mandrel.

FIGURE 7 is a view similar to FIGURE 6 showing the mandrel in expandedform.

FIGURE 8 is a sectional view of the guide used for contracting themandrels, the position of the section being indicated by the line SS ofFIGURE 1.

FIGURE 9 is a diagrammatic view of the guide for expanding the mandrels.

FIGURE 10 is a diagrammatic collapsing the mandrels.

In the present invention, the apparatus is shown diagrammatically ratherthan in detail, as it is believed that a better understanding of theinvention may be obtained from the diagrammatic views. It is felt thatthe showing is sufficiently clear to permit one skilled in the art toproduce the apparatus, and this has been indicated by the fact that theprototype was constructed from similar sketches.

An important feature of the invention resides in expanding the bags 10while the bags are connectedlightly by spots of adhesive indicated at11. In general, the bags may be of any suitable type which can fold toform a square end, the bags in question including a generallyrectangular side wall 12., a pair of side wall panels 13 which overlapto form a single rectangular side wall similar in size to the wall 12,and rectangular gusset panels 14 of similar size connecting the freeedges of the side walls i2 and 13. The ends of the tube thus formed isfolded upon itself to form a seam 15 which closes the end of the bag. Asa result, the side walls 12 and 13 are normally in fiat contiguousrelation with the two gusset flaps 14 folded between the sides of thepanels 12 and 13. However, when squared up, portions of the gussetpanels fold along diagonal fold lines to form a square bottom as is wellknown in the art.

The flat bags are thus provided in stacks, each bag being connected tothe next bag by a small spot of adhesive 11 which may be severe-d orwhich will break before the material forming the bag will tear. Wheneach series of connected bags is placed in the feeding hopper 15 of theapparatus shown in FIGURE 1, a spot of adhesive is applied between theend bags of the adjoining surfaces so as to provide a continuous chainof bags. The apparatus includes an elongated conveyor supported by apair of parallel shafts 17 and 19 which support sprockets or pulleys 20and 21 respectively supporting a pair of parallel chains or belts 22.The chains 22 support a series of expandable and contractible mandrels23 which are of assistance in opening the bags 10.

As is diagrammatically illustrated in FIGURES 4-8, the mandrels 23include a pair of side plates 24 pivotally connected at 25 to a crossmember 26 secured in any suitable way to the chains or belts 22. Theplates 24 are movable from an upwardly and inwardly converging relationas shown in FIGURES 4 and 6 to parallel relation as indicated in FIGURES5 and 7. The side plates 24 are inserted into the bags 10 while inplanes substantially normal to the planes of the bag sides. In otherwords, these plates 24 are substantially the width of the view of themeans of connected gusset panels of the bag, and are arranged to foldthe gusset panels outwardly into a common plane throughout the depth ofthe bag.

The mandrels 23 ride over a guide plate 27 having side flanges 29 whichare spaced apart a distance sufficient to permit the side plates 24 toconverge inwardly in the manner shown in FIGURE 6 at the inlet end 30 ofthe guide track which is adjacent the hopper 16. As indicated in FIGURE9, these flanges 29 converge together to midpoint 31 at which point theflanges are sufficiently close to have swung the plates 24 into parallelrelation. When in this position, the walls of the bag are squared upinto generally rectangular form.

As indicated in FIGURE 1 of the drawings, a pair of V endless belts 32which are traveling at approximately the same speed as the bags on theconveyor engage the gusset flaps 14 of the bag and press them againstthe mandrel plates 24. As illustrated in this figure, the endless belts32 are arranged at an angle to the horizontal path of the mandrels andtherefore frictionally engage the bags and draw them downwardly over themandrel structure. Thus while the bags are only partially down on themandrels at the start of the operation, they are pulled downwardly tothe full depth of the bag by the endless belts 32 arranged on both sidesof the conveyor belts or chains 22.

The mandrels 23 are provided with a collapsible end designed to form aplatform against which the ends of the bags may be pressed. While thisarrangement is usually of the positive functioning type such as a pairof toggle plates, in the simple arrangement illustrated, the endplatform forming member 34 is hingedly connected at 35 to the upper endof one of the plates 24, the plate 34 together with the side plates 24forming a rectangular mandrel which substantially fills the bag 10. Abearing 36 which may include a spring supports a plunger 37 having anupper end 39 which bears against the plate 34 and a lower end 40 whichmay slide along the surface of the guide plate 27, and over a cam rail41 near the end of the upper reach of the conveyor. In any event, aseach mandrel nears the end of the upper reach of the conveyor and whenthe bags have been pulled downwardly on the mandrels, the end plate 34forms a platform or table against which the bottom of the bag may bepressed. A pressing or sealing belt 43 is supported by suitable pulleys44 mounted on parallel shafts 45 parallel to the shafts 17 and 19supporting the conveyor 22. If the bags are of heat sealable material,the belt 43 may Y comprise a heated belt which presses the bag endagainst 'in their expanded form as the mandrels travel about thesprockets 2i) and then diverge outwardly toward the outlet end of theguide plate as indicated at 50. The outward divergence of the flanges 47permit the side plates 24 of the mandrels 23 to collapse to the relationillustrated in FIGURE 8 and to insure the collapse of the mandrels,inner guide flanges 51 which also diverge and which are parallel to thediverging flanges 47 swing the mandrels toward their collapsed position.

' A means is provided for removing the bags from the mandrels andconveying them to a filling mechanism or the like. In the arrangementillustrated, this structure comprises a perforated belt 52 supported bya pair of sup- I porting pulleys 32 mounted on parallel shafts 54 andlocated beneath the conveyors 22 and the mandrels carried thereby. Asuction box 55 having an open top or having a perforated top liesbeneath the upper reach of the belt 52,

and the bags 10 are drawn by this partial vacuum on to the belt 52. Thebelt 52 is arranged in divering relation'to the conveyor belts 22 sothat upon movement of the belt 52 in timed relation with the conveyorchains 22, the bags 10 are withdrawn from the mandrels 23 and areconveyed to a suitable destination. Due to the flat squ-are ends on thebags, they are quite stable during this conveying operation.

In the operation of the apparatus, the bags are placed in a suitablehopper, and in the arrangement illustrated are supported with their openends downwardly and in a generally vertical position. The foremost bagof the series is placed over the upper end of one of the mandrels, andthe movement of the conveyor chains 22 acts to draw the bags one at atime over the spaced mandrels, the movement of the bags being restrictedby suitable means at the end of the hopper so as to release the bags oneat a time, and to open the bags to a certain extent before they arecompletely released. After a predetermined period of travel during whichthe bags .move farther down on the mandrels, the mandrels are expandedby the flanges 29 of the guide plate 27, the mandrel plates 24 foldingthe gusset planes 14 into a common plane and swinging the bag sides 12and 13 into parallel relation. This action causes the adhesive bond 11between adjoining bags to break. Furt-her travel of the mandrel bringsthe endless friction'belts 32 against the sides of the bag, and thedownward inclination of the belts 32 causes the bag to be pulled downover the mandrels. At about this time the end plates 34 are swung upinto right angular relation to the sides 24 and the ends of the bag aresealed or flattened by the belt 43 which travels at the same speed asthe conveyor chains 22.

The mandrels are maintained in expanded condition until the bags areinverted at which time the mandrels are collapsed by the guide flanges51 and the bags are drawn on to the perforated belt 50 by action of thesuction box 55. The squared up open bags are then delivered to asuitable conveyor and to a desired destination.

In accordance with the patent statutes, I have described the principlesof construction and operation of my improvement in method and apparatusfor expanding bags, and while I have endeavored to set forth the bestembodiment thereof, I desire to have it understood that changes may bemade within the scope of the following claims without departing from thespirit of my invention.

I claim:

1. A bag opening apparatus for use in combination with a series ofcontiguous bags arranged in flat face contact, the bags having a closedend and an open end, and the bags being connected in a chain byseparable spots of adhesive between the sides of the bags near the openend thereof, the apparatus including a hopper for supporting said bagsin face contact,

a series of mandrels engage able into the open ends of said bags to holdthe bags open,

means supporting said mandrels in spaced relation for movement about anendless path,

means for moving said mandrels about said path while engaged in at leastone bag acting to successively open said bags in said chain, and

means guiding the bags of said chain successively on to said mandrels asthey are drawn from said hopper.

2. The structure of claim 1 and including means for separating theadhesive connection between said bags as they are carried by saidmandrels.

3. The structure of claim 2 and including means for removing saidseparated bags from said mandrels. V 4. A bag opening apparatus'for usewith bags each havmg a pair of side panels having parallel side edgesconnected by pairs of gusset panels and having an end seam forming aclosed bag with: opposite ends of said panels being open, the bags beingfoldable from flat form in which the gusset panels are sandwichedbetween the side panels to a rectangular expanded form, the side panelsof Id 23 the adjoining bags being connected intermediate their sideedges and adjoining their open ends by spots of adhesive to provide achain or" bags, the apparatus including,

a hopper for supporting the chain of bag an endless conveyor supportinga series of equally spaced aligned mandrels thereupon, the spacingbetween the centers of said mandrels being somewhat greater than thecombined width of said gusset panels on each of said side panels, saidmandrels being collapsible toward one another in a directiontransversely of the direction of travel of said mandrels, whereby saidbags may be elongated in the direction of travel thereof as the bags areapplied over said mandrels while connected in a chain, and

means for expanding said mandrels to fold said bag panels intorectangular expanded form, thereby pulling the adhesive connectionbetween said bags apart and squaring up the individual bags. 5. Thestructure of claim 4 and including means for drawing the bags over themandrels to substantially the full depth of the bag.

6. The structure of claim 4 and including means for folding the bag endsinto fiat form over the mandrel ends.

7. The structure of claim 4 and including a pair of inclined conveyorbelts engaging the bags on the mandrels and drawing them over themandrels to substantially the full depth of the bags.

8. A bag opening apparatus for use with bags each having a pair of sidepanels having parallel side edges connected by pairs of gusset panelsand having an end seam forming a closed bag end, the opposite end ofsaid panels being open, the bags being foldable from flat form in whichthe gusset panels are sandwiched between the side panels to arectangular expanded form, the side panels of the adjoining bags beingconnected intermediate their side edges and adjoining their open ends byspots of adhesive to provide a chain of bags, the apparatus including,

a hopper for supporting the chain of bags, an endless conveyorsupporting a series of equally spaced aligned mandrels thereupon, thespacing between the centers of said mandrels being somewhat greater thanthe combined width of said gusset panels on each side of said sidepanels, said mandrels each including a pair of plates pivotallysupported upon said conveyor on pivots parallel to the direction oftravel of the conveyor and movable from a position in which the ends ofthe plate most remote from the conveyor converge together to a parallelposition, said plates when in parallel position being spaced apart adistance substantially equal to the width of the side walls and saidplates being of a width substantially equal to the combined width ofsaid gusset panels,

said hopper being so located relative to said conveyor to permit thebags to be drawn one by one on to the mandrels while the plates are inconverging position, said bags being elongated in the direction oftravel of the mandrels beyond the width of the plates while still in acontinuous chain, and

means for successively swinging said plates into said parallel positionas the mandrels travel with said conveyor to fold the bags successivelyinto rectangular expanded form.

9. The structure of claim 8 and including means engaging the portions ofsaid bags which are in face contact with said plates to draw the bagsfarther on to said mandrels.

10. The structure of claim 8 and in which the mandrels include an endforming member forming an end wall between said ends of said plates whenthe plates are in parallel relation, and

means engageable with the closed ends of the bags carried by saidmandrels for flattening the bag ends against said end forming members.

11. A bag opening apparatus for use with bags each having a pair of sidepanels having parallel side edges connected by pairs of gusset panelsand having an end seam formin a closed bag end, the opposite ends ofsaid panels being open, the bags being foldable from flat form in whichthe gusset panels are sandwiched between the side panels to arectangular expanded form, the side panels of the adjoining bags beingconnected intermediate their side edges and adjoining their open ends byspots of adhesive to provide a chain of bags, the apparatus including,

an endless conveyor supported by a pair of parallel horizontal axes andhaving an upper reach and a lower reach,

a series of spaced mandrels mounted in spaced relation on said conveyorand collapsible transversely of the conveyor,

said mandrels in expanded form being of a size substantially equal tothe inner dimensions of the individual bags,

a hopper at one end of said conveyor supporting said bags with the openends thereof directed downwardly toward the upper reach of the conveyor,and including means guiding the open bags over the successive mandrelswhen connected as a chain,

me ans maintaining the mandrels in collapsed form while the bags are atleast partially inserted thereover,

means successively expanding said mandrels while the bags are supportedthereby to fold them into rectangular form, and holding said bagsexpanded as the mandrels travel about the axis at the end of the upperreach of the conveyor, moving the bags into upright position,

conveying means beneath the lower reach of the conveyor to convey theexpanded bags, and means collapsing said mandrels as they pass over saidconveying means to release the bags therefrom.

12. The structure of claim 11 and including means engageable with thebags on the expanded mandrels for insuring the insertion of the mandrelsinto the bags to the full depth of the bags.

13. The structure of claim 12 and including means engageable with theclosed ends of the bags While on said expanded mandrels to flatten thebag ends into a plane generally normal to the planes of the remainder ofthe bag panels.

References Cited by the Examiner UNITED STATES PATENTS 515,121 2/1894Hunt 9335 1,368,633 2/1921 Johnson 93-35 2,437,117 3/ 1948 Orstrom 533842,601,480 6/1952 Williams 53-384 2,653,751 9/1953 Vogt 22953 2,671,6023/1954 Vogt 22-953 FRANK E. BAILEY, Primary Examiner.

1. A BAG OPENING APPARATUS FOR USE IN COMBINATION WITH A SERIES OFCONTIGUOUS BAGS ARRANGED IN FLAT FACE CONTACT, THE BAGS HAVING A CLOSEDEND AND AN OPEN END, AND THE BAGS BEING CONNECTED IN A CHAIN BYSEPARABLE SPOTS OF ADHESIVE BETWEEN THE SIDES OF THE BAGS NEAR THE OPENEND THEREOF, THE APPARATUS INCLUDING A HOPPER FOR SUPPORTING SAID BAGSIN FACE CONTACT, A SERIES OF MANDRELS ENGAGEABLE INTO THE OPEN ENDS OFSAID BAGS TO HOLD THE BAGS OPEN, MEANS SUPPORTING SAID MANDRELS INSPACED RELATION FOR MOVEMENT ABOUT AN ENDLESS PATH, MEANS FOR MOVINGSAID MANDRELS ABOUT SAID PATH WHILE ENGAGED IN AT LEAST ONE BAG ACTINGTO SUCCESSIVELY OPEN SAID BAGS IN SAID CHAIN, AND MEANS GUIDING THE BAGSOF SAID CHAIN SUCCESSIVELY ON TO SAID MANDRELS AS THEY ARE DRAWN FROMSAID HOPPER.